Director James Cameron’s ground breaking 3D film Avatar has held the top worldwide box-office spot since its release in 2009. But in Hong Kong, even the beloved blue Na’vi couldn’t defend Avatar’s opening day earning record, which has just been shattered by a campy soft-core porn film.

According to NPR, 3D Sex and Zen: Extreme Ecstasy brought in more money on its first day than any other film to open in Hong Kong. While Avatar generated HK$2.63 million opening day, Sex and Zen grossed a whopping HK$2.78 million (about $340,000 in US dollars) while showing on 73 screens. And its popularity only continued, bringing in about HK$17 million during its opening weekend.

Sex and Zen is based a 1991 film of the same name (which, in turn, is based on an ancient novel entitled The Carnal Prayer). The film’s story is about a “frustrated” teacher in ancient China who becomes overly smitten by the harem of his aristocratic friend.

The film stars Japanese porn actresses Hara Saori and Suo Yukiko, and Hong Kong actress Vonnie Liu. Billed as “the world’s first 3-D erotic film,” Sex and Zen features full nudity and “camouflaged lovemaking,” but leaves the more salacious details to the imagination.

The film has also done well in neighboring Taiwan, where it earned 17 million New Taiwan Dollars ($590,000) during its opening weekend there. That figure, however, was not enough to knock Avatar off its high horse there.

According to the film’s producer, Stephen Shiu, the idea long-held idea that pornography is the perfect genre for 3D films played a vital role in the initial success of Sex and Zen.

“We met people’s expectations,” Shiu told NPR in an interview. “People have always thought that you need 3D technology for this kind of content. So people were very curious.”